CVE-2021-40656

libsixel before 1.10 is vulnerable to Buffer Overflow in libsixel/src/quant.c:867.

CVE-2021-45340

In Libsixel prior to and including v1.10.3, a NULL pointer dereference in the stb_image.h component of libsixel allows attackers to cause a denial of service (DOS) via a crafted PICT file.